1. Technical Field
The invention relates to cleaning systems and, in particular, to a cleaning system for a meat processing machine. More particularly, the invention relates to a system which produces momentary bursts of pressurized fluid against and along a rotating tooth roll to dislodge and remove particles from the roll as the roll rotates past the nozzles while removing skin and other particles from meat.
2. Background Information
Various equipment in the meat processing industry use tooth rolls for removing skin and other particles from a piece of meat which is fed, either manually or automatically, past the rotating roll. One problem that is encountered with such tooth meat stripping rolls is that they quickly become clogged with skin, meat particles, fat and the like, reducing considerably their efficiency in a relatively short period of time. This requires stopping the machine and manually removing the collected particles from the roll teeth.
Various types of cleaning systems have been devised for removing such particles from the tooth rolls without interrupting the meat processing operation. One type of system is shown in U.S. Pat. No. 4,807,321. This system provides air nozzles which are moved axially along the rotating tooth roll so that pressurized air is discharged from the nozzles against the rotating roll to remove particles therefrom. Although this apparatus may provide some cleaning of the tooth roll, it requires a number of moving parts and requires pressure seals which are subject to leakage. It also requires a relatively large volume of pressurized air in relationship to the number of nozzles in order to provide a sufficient cleaning system.
Another type of cleaning system using pressurized air which is impinged against the work being cleaned is shown in U.S. Pat. No. 3,571,840, and is used in the textile industry. In this prior system, a plurality of nozzles are oscillated back and forth across the roll being cleaned. In order to reduce the volume of pressurized air, the system has either a sliding plate or a hollow internal rotating cylinder which selectively opens and closes the inlets to the nozzles so that only one or several of the nozzles are being supplied with the pressurized air at any one time. This reduces the amount of pressurized air required, and reduces the size of the air supply system and power to provide the same. However, with this textile cleaning system, the nozzles are oscillated back and forth requiring additional motive power. Furthermore, such a system requires a relatively large internally rotating drum or sliding plate which requires increased power to operate the mechanical mechanism, in addition to the extra power required to oscillate the nozzles across the rotating roll.
Although the use of only pressurized air impinged against the rotating roll of a meat skinning machine is satisfactory for moving most of the trapped meat particles, it has been found that the use of jets of pressurized water impinged against the roll has increased cleaning ability to dislodge and remove the meat particles trapped between the teeth of the rotating roll.
Although these water cleaning systems increase the cleaning efficiency on the roll in contrast to those systems using only streams of high pressure air, they require a considerable amount of water and equipment for pressurizing the water, which increases considerably the cost of operating the cleaning system. Such prior water cleaning systems require the initial supply of water to the cleaning mechanism, as well as additional equipment for collecting and removing the large amounts of spent water, for subsequent discharge into a sewage system, which increases the total cost of the system, or requires expensive recirculating and processing equipment for cleaning such large amounts of spent water for subsequent use, in a closed water cleaning system.
None of the known prior art cleaning machines provide for pressurized air which is impinged against the roll of a meat cleaning machine to be supplied with relatively small amounts of water which is mixed with the pressurized air just prior to it being discharged from the spray nozzle, whereby a mixture of pressurized air and water is discharged from the cleaning nozzles and impinged against the rotating roll to remove the meat particles therefrom.
Therefore, the need has existed for an improved cleaning system for meat processing machines in which the cleaning system is operable during the process to provide for continuous cleaning of the meat or skin removing roll, which does not interfere with the cleaning operation, which requires a minimum volume of pressurized fluid to clean the roll, and which requires a minimum number of moving parts and eliminates maintenance prone moving air seals.